Multicell Random Beamforming with CDF-based Scheduling: Exact Rate and Scaling Laws

TL;DR

This paper analyzes multicell multiuser MIMO downlink systems employing random beamforming and CDF-based scheduling, deriving exact rate expressions and asymptotic scaling laws to understand system performance under interference.

Contribution

It extends previous analyses to multicell scenarios, providing closed-form rate expressions and asymptotic scaling laws for distributed scheduling with interference.

Findings

Derived exact individual sum rate expressions.

Established asymptotic distribution of SINR.

Determined individual user scaling laws.

Abstract

In a multicell multiuser MIMO downlink employing random beamforming as the transmission scheme, the heterogeneous large scale channel effects of intercell and intracell interference complicate analysis of distributed scheduling based systems. In this paper, we extend the analysis in [1] and [2] to study the aforementioned challenging scenario. The cumulative distribution function (CDF)-based scheduling policy utilized in [1] and [2] is leveraged to maintain fairness among users and simultaneously obtain multiuser diversity gain. The closed form expression of the individual sum rate for each user is derived under the CDF-based scheduling policy. More importantly, with this distributed scheduling policy, we conduct asymptotic (in users) analysis to determine the limiting distribution of the signal-to-interference-plus-noise ratio, and establish the individual scaling laws for each user.